MSS50-1200

Overview

The MSS50-1200 is a back-to-back Silicon Controlled Rectifier (SCR) module manufactured by STMicroelectronics. It features an ISOTOP isolated package designed for through-hole mounting. The device supports a rated repetitive off-state voltage of 1200 V and handles a non-repetitive on-state current of up to 630 A. Key electrical characteristics include a maximum gate trigger voltage of 1.5 V and a maximum gate trigger current of 50 mA. The module maintains a maximum holding current of 80 mA, ensuring reliable latching in high-power AC switching applications.

Feature Summary

• Back-to-back SCR configuration for bidirectional AC control
• ISOTOP isolated package for thermal management and safety
• High surge current capability for robust operation
• Low gate trigger requirements for efficient drive circuits

Applications

• AC phase control for resistive and inductive loads
• Industrial motor speed control systems
• High-power heating element regulation
• Welding equipment power supplies

Procurement Notes

Verify component authenticity through authorized distributors or official manufacturer channels due to obsolete status. Confirm package integrity and pin alignment against original specifications. Request batch-specific test reports if available. Ensure storage conditions comply with semiconductor handling standards to prevent moisture damage prior to assembly.

Selection Notes

Evaluate thermal resistance requirements against the ISOTOP package capabilities for the specific application load. Compare gate trigger parameters with available driver circuitry to ensure reliable turn-on. Assess mechanical clearance for the through-hole mounting style. Consider voltage derating factors based on peak line voltages and transient spikes in the target system environment.

Part Context

This component belongs to the MSS50 series of general-purpose SCR modules from STMicroelectronics. The series is engineered for AC switching and phase control applications operating at frequencies up to 400 Hz. These modules integrate two SCRs in a single isolated package, simplifying design complexity for high-power single-phase controllers while maintaining compact form factors.

Replacement Considerations

Public records indicate the MSS50-1200 is discontinued. Similar substitutes may include other MSS50 series variants with compatible voltage ratings, such as the MSS50-800 or MSS50-1400, provided electrical parameters align with system requirements. Verify pinout compatibility and thermal performance before substitution.